6 files changed, 135 insertions, 2 deletions
diff --git a/lib/psych.rb b/lib/psych.rb
index 74da20a..9b9a079 100644
--- a/lib/psych.rb
+++ b/lib/psych.rb
@@ -14,6 +14,7 @@ require 'psych/handler'
 require 'psych/tree_builder'
 require 'psych/parser'
 require 'psych/ruby'
+require 'psych/omap'
 require 'psych/psych'
 
 module Psych
diff --git a/lib/psych/omap.rb b/lib/psych/omap.rb
new file mode 100644
index 0000000..6286270
--- /dev/null
+++ b/lib/psych/omap.rb
@@ -0,0 +1,4 @@
+module Psych
+  class Omap < ::Hash
+  end
+end
diff --git a/lib/psych/visitors/to_ruby.rb b/lib/psych/visitors/to_ruby.rb
index 3b2d7f7..dbe4a39 100644
--- a/lib/psych/visitors/to_ruby.rb
+++ b/lib/psych/visitors/to_ruby.rb
@@ -69,8 +69,17 @@ module Psych
       def visit_Psych_Nodes_Sequence o
         list = []
         @st[o.anchor] = list if o.anchor
-        o.children.each { |c| list.push accept c }
-        list
+        case o.tag
+        when '!omap', 'tag:yaml.org,2002:omap'
+          map = Psych::Omap.new
+          o.children.each { |a|
+            map[accept(a.children.first)] = accept a.children.last
+          }
+          map
+        else
+          o.children.each { |c| list.push accept c }
+          list
+        end
       end
 
       def visit_Psych_Nodes_Mapping o
diff --git a/test/yaml/test_boolean.rb b/test/yaml/test_boolean.rb
new file mode 100644
index 0000000..7bc474e
--- /dev/null
+++ b/test/yaml/test_boolean.rb
@@ -0,0 +1,36 @@
+require 'helper'
+
+module YAML
+  ###
+  # Test booleans from YAML spec:
+  # http://yaml.org/type/bool.html
+  class TestBoolean < Test::Unit::TestCase
+    %w{ yes Yes YES true True TRUE on On ON }.each do |truth|
+      define_method(:"test_#{truth}") do
+        assert_equal true, YAML.load("--- #{truth}")
+      end
+    end
+
+    %w{ no No NO false False FALSE off Off OFF }.each do |truth|
+      define_method(:"test_#{truth}") do
+        assert_equal false, YAML.load("--- #{truth}")
+      end
+    end
+
+    ###
+    # YAML spec says "y" and "Y" may be used as true, but Syck treats them
+    # as literal strings
+    def test_y
+      assert_equal "y", YAML.load("--- y")
+      assert_equal "Y", YAML.load("--- Y")
+    end
+
+    ###
+    # YAML spec says "n" and "N" may be used as false, but Syck treats them
+    # as literal strings
+    def test_y
+      assert_equal "n", YAML.load("--- n")
+      assert_equal "N", YAML.load("--- N")
+    end
+  end
+end
diff --git a/test/yaml/test_null.rb b/test/yaml/test_null.rb
new file mode 100644
index 0000000..24c8ab1
--- /dev/null
+++ b/test/yaml/test_null.rb
@@ -0,0 +1,19 @@
+require 'helper'
+
+module YAML
+  ###
+  # Test null from YAML spec:
+  # http://yaml.org/type/null.html
+  class TestNull < Test::Unit::TestCase
+    def test_null_list
+      assert_equal [nil] * 5, YAML.load(<<-eoyml)
+---
+- ~
+- null
+- 
+- Null
+- NULL
+      eoyml
+    end
+  end
+end
diff --git a/test/yaml/test_omap.rb b/test/yaml/test_omap.rb
new file mode 100644
index 0000000..d3d7fde
--- /dev/null
+++ b/test/yaml/test_omap.rb
@@ -0,0 +1,64 @@
+require 'helper'
+
+module YAML
+  class TestOmap < Test::Unit::TestCase
+    def test_keys
+      map = YAML::Omap.new
+      map['foo'] = 'bar'
+      assert_equal 'bar', map['foo']
+    end
+
+    def test_order
+      map = YAML::Omap.new
+      map['a'] = 'b'
+      map['b'] = 'c'
+      assert_equal [%w{a b}, %w{b c}], map.to_a
+    end
+
+    def test_square
+      list = [["a", "b"], ["b", "c"]]
+      map = YAML::Omap[*list.flatten]
+      assert_equal list, map.to_a
+      assert_equal 'b', map['a']
+      assert_equal 'c', map['b']
+    end
+
+    def test_to_yaml
+      map = YAML::Omap['a', 'b', 'c', 'd']
+      yaml = map.to_yaml
+      assert_match('!omap', yaml)
+      assert_match('- a: b', yaml)
+      assert_match('- c: d', yaml)
+    end
+
+    def test_round_trip
+      list = [["a", "b"], ["b", "c"]]
+      map = YAML::Omap[*list.flatten]
+      loaded = YAML.load(YAML.dump(map))
+
+      assert_equal map, loaded
+      assert_equal list, loaded.to_a
+    end
+
+    def test_load
+      list = [["a", "b"], ["c", "d"]]
+      map = YAML.load(<<-eoyml)
+--- !omap
+- a: b
+- c: d
+      eoyml
+      assert_equal list, map.to_a
+    end
+
+    # NOTE: This test will not work with Syck
+    def test_load_shorthand
+      list = [["a", "b"], ["c", "d"]]
+      map = YAML.load(<<-eoyml)
+--- !!omap
+- a: b
+- c: d
+      eoyml
+      assert_equal list, map.to_a
+    end
+  end
+end